366 W. G. Van Name — Bermuda Ascidians, 



Var. somersi, nov. 



Plate LII. Figure 48. Plate LXII. Figure 136. 



Forms very small (10 to 20""" wide), flat colonies of a pure white 

 color. The}^ are very thin (often under \"^^^\ and not very opaque. 

 The zooids are as small as those of var. acutilohatuDi. They are 

 placed rather far apart. The spicules are large (fig. 48), with 

 regular conical points of some length, and are evenly but often not 

 very closely distributed in the colony. The positions of the zooids 

 are very conspicuous from the surface, though the apertures are not 

 especially so. There is but one common cloacal aperture to the 

 colony. The branchial apertures of the zooids have pointed lobes 

 but much shorter ones than those of the last described form. 



Quite generally distributed, though not very abundant. 



Genus Polysyncraton Nott, 1891. 



Separated from Leptoclimim (which it resembles in having four 

 rows of stigmata) by having a number (sometimes as many as 10) 

 of distinct j^yriform testes, arranged in a circle, forming together a 

 conical group, about which the vas deferens makes a few spiral 

 turns : and by possessing an atrial languet. 



The type of the genus is from New Zealand (13). 



Polysyncraton amethysteum, n. sp. 



Plate LIV. Figures 62 and 64 to 67 inclnsive. Plate LVIII. Figure 102. 



Colony more or less transparent except for a thin layer of spicules 

 on the upper surface. The test is of an amethyst purple or rose 

 purple tint, due to pigment contained in the test cells, while the 

 tissues of the zooids are bright red. These colors fade out in pre- 

 servation, the test becoming yellowish and the zooids yellow or 

 orange. The colonies seldom exceed 30™™ in width and 3 or 3.5™™ 

 in thickness. 



The layer of white spicules on the upper surface of the colony 

 shows in strong contrast to the colors of the test. It may readily be 

 stripped off. The spicules are entirely confined to it. Large areas 

 about the common cloacal openings are entirely bare of spicules, 

 also small oval areas about the branchial orifices, but in these latter 

 may be seen small V-shaped groups of spicules, six in number in 

 each, corresponding to the six lobes of the branchial siphons. This 

 arrangement of the spicules about the branchial openings occurs 



